views: Make view::Views::GetPreferredSize() const.

ui/views/controls/single_split_view.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_CONTROLS_SINGLE_SPLIT_VIEW_H_
 #define UI_VIEWS_CONTROLS_SINGLE_SPLIT_VIEW_H_
 
 #include "base/gtest_prod_util.h"
 #include "ui/views/view.h"
 
@@ skipping 20 matching lines @@
                   Orientation orientation,
                   SingleSplitViewListener* listener);
 
   virtual void Layout() OVERRIDE;
   virtual const char* GetClassName() const OVERRIDE;
 
   virtual void GetAccessibleState(ui::AXViewState* state) OVERRIDE;
 
   // SingleSplitView's preferred size is the sum of the preferred widths
   // and the max of the heights.
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
 
   // Overriden to return a resize cursor when over the divider.
   virtual gfx::NativeCursor GetCursor(const ui::MouseEvent& event) OVERRIDE;
 
   Orientation orientation() const {
     return is_horizontal_ ? HORIZONTAL_SPLIT : VERTICAL_SPLIT;
   }
 
   void set_orientation(Orientation orientation) {
     is_horizontal_ = orientation == HORIZONTAL_SPLIT;
@@ skipping 86 matching lines @@
 
   // The accessible name of this view.
   base::string16 accessible_name_;
 
   DISALLOW_COPY_AND_ASSIGN(SingleSplitView);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_SINGLE_SPLIT_VIEW_H_